Mini Speedster Biplane V.3
Well folks, here is the finished project and I couldn't be more pleased! It flies really well and the build isn't all that complicated so with a little extra effort you too could have a mini speedster biplane. The final project has a wingspan of 24" with a chord of 4". The fuselage is a total of 3" longer than the Mini Speedster, 2" longer in the tail, and 1" longer in the nose. It now has ailerons on all four wings, I tried with just lower ailerons but it just wasn't enough, and adding the top ailerons is very simple. The bottom wing has a 0 degree incidence while the top wing has 2 degrees positive incidence.
Here are the plans that I modified from the Mini Speedster. The tail is enlarged as well but I just went for what looked about right, nothing scientific here.
Here is how I mounted the BBQ skewer cabane struts. Basically I just made a 3 piece former with the center piece cut with 15 degree angles. Then I poked the skewers through the fuselage and glued them together where they met.
The wings are very simple to make, I cut two pieces at 24" by 4" and created the camber at 1.5" back from the leading edge, then cut the rounded curve ends. Then just build them with the same method as the SE5. The struts took some time to measure out and make. You'll need a ruler and some descent protractor skills. The basic dimensions are 4.5" by 2.5" and they slant forward to give the wings their stagger 1". I then measured out where I wanted the taps to line up with slots in the wing, your discretion on placement. I used .5" tabs and the front tab is .5" in front of the camber line and the rear tab is 1" behind the camber line. I then measure in 2 degrees positive incidence. Then draw in the cross bracing, I like the traditional N brace style. It sounds confusing but hopefully the pictures make it a little easier to understand.
The sheeting is very much the same as any other FT plane, although I did add a 3rd piece to make it all fit around the struts. You can also see in these pictures how the bottom wing is mounted. Very simple, just cut the bottom of the fuselage to match the wing and glue it straight to the bottom. I did add one crosspiece in front of the wing to ensure that the fuselage remained straight while attaching the wing.
Here is how I set up the ailerons. Very simple and only uses one servo. For the cross bars to the top ailerons, I used cut off servo horns glued into the trailing edge. Very clean install and works like a charm!
That pretty much covers it, if you have questions feel free to ask!
One more thing, I would like to add a windshield but I would like to make it removable so that I can fly it FPV without. Anybody have any bright ideas?